Gun.



J. H. BROWN.

GUN.

APPLICATION FILED T11R16, 1910.

Patented July 11,1911.

mummy PLANoaBAm-l Cm, WASHINGTON, D. c.

UNITED @TAIES PAEENT FFIQE JOHN H. BROWN, OF WEST HOIBOKEN, NEW JERSEY.

GUN.

To all whom it may concern:

Be it known that I, JOHN H. BROWN, a citizen of the United States, and resident of Vest I-Ioboken, in the county of Hudson and State of New Jersey, have invented a new and useful Improvement in Guns, of which the following is a specification.

My invention relates to guns and more particularly to the structure of the bore along that portion leading forward from the powder chamber, with the object in View to com pensate for the expansion or enlargement of the bore under the intense pressure of the explosive charge and thereby prevent the gases resulting from the explosion from rushing past the projectile and scoring the wall of the bore.

A practical embodiment of the invention is represented in the accompanying drawings in which- Figure 1 is a view in longitudinal section of the forward end of the powder chamber and a portion of the chase of the gun in proximity thereto, and Fig. 2 is an exaggerated view in detail illustrating the enlargement of the bore under intense internal pressure.

It has been ascertained by careful calcu lation that the bore of a gun under the intense pressure of the explosive charge will reach its maximum enlargement after the projectile has traveled a considerable distance along the chase, this point of maximum enlargement varying in different guns according to the thickness and quality of the metal which forms the gun barrel, and the character of the explosive.

My present invention contemplates tapering the bore of the gun gradually reducing the size of the bore from the front of the powder chamber forward to a point where the maximum enlargement of the bore takes place in firing, the line of taper corresponding as closely as may be to the gradual enlargement of the bore from the moment of explosion up to the maximum enlargement so that a projectile provided with a band which will hold the gases from the explosive charge from passing the projectile at the moment of explosion will oppose the same Specification of Letters Patent.

Application filed February 16, 1910.

Patented July 11, 1911.

Serial No. 544,216.

effective resistance to the passing of the gases up to as well as beyond the point of maximum enlargement.

The tapered front end of the powder chamber is denoted by 1 and the tapered portion of the'chase from the front end of the powder chamber to the point where the maximum enlargement takes place, by 2. In the present instance the drawing is taken from a gun actually constructed and tested, the diameter of the bore in this particular gun at the point 3 where the maximum expansion takes place being 2.244 inches and at the front 4 of the powder chamber 2.394 inches, the length of the tapered portion during which the pressure increases from the moment of explosion of the charge up to the moment of the highest pressure being 10 inches.

From the point 3 of maximum expansion, the expansion .of the bore will gradually diminish to the muzzle of the gun, so that if the gases resulting from the explosion are effectually restrained from getting past the projectile up to the point 3, the band which has held them in check to this point may be relied upon to effectually restrain them throughout the remainder of the chase.

The exaggerated illustration, Fig. 2, shows the relative lines of expansion and taper, the line of taper which the bore of the tapered portion normally assumes being denoted by 5, and the line of expansion by 6, showing the wall under expansion substantially parallel with the longitudinal axis of the bore, the taper of the bore being intentionally made of such pitch that the amount of expansion at any point will not carry the wall of the bore outwardly far enough to increase the diameter of the bore over and above the diameter at the front end of the powder chamber where the taper of the chase begins.

.Vhat I claim is:

A gun having its bore tapered forward from the powder chamber for a distance corresponding in length to the distance traveled by the projectile from the moment of explosion of the firing charge to the moment when the pressure of the firing charge reaches its maximum, the pitch line of taper corresponding as closely as may be to the presence of tWo Witnesses, this fifteenth day gradual enlargement of the bore during the of February 1910.

gradually increasing pressure from the moment of explosion up to the maximum pres- JOHN sure. Witnesses:

In testimony, that I claim the foregoing as F. GEORGE BARRY, my invention, 1 have signed my name in HENRY C. THIEME.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

